Reshaping dies for freshly molded pulp articles



Aug- 15, 1961 M. P. cHAPLlN 2,996,118

RESHAPING DIES FOR FRESHLY MOLDED PULP ARTICLES Original Filed Sept. 29, 1953 5 Sheets-Sheet 1 INVENTOR EPLE P. CHnPL/N ATTORNEY Aug. 15, 1961 M. P. cHAPLlN 2,996,118

RESHAPING DIES FOR FRESHLY MOLDED PULP ARTICLES Original Filed Sept. 29, 1953 3 Sheets-SheeI 2 INVENTOR MEME P HF/PHN a@ i. y. Q.

ATTORNEY Aug. 15, 1961 M. P. cHAPLlN RESHAPING DIES FOR FRESHLY MOLDED PULP ARTICLES Original Filed Sept. 29, 1953 5 Sheets-Sheet 3 NNN INVENTOR ATTORNEY /WEQLE P www United ftates Patent 2,996,118 RESHAPING DIES FOR FRESHLY MOLDED PULP ARTICLES Merle P. Chaplin, South Portland, Maine, assigner, by mesne Iassignments, to Diamond National Corporation, New York, N.Y., a corporation of Delaware Original application Sept. 29, 1953, Ser. No. 382,985, now Patent No. 2,938,582, dated May 31, 1960. Divided and this application June 17, 1959, Ser. No. 820,992

18 Claims. (Cl. 162-396) This application is a division of my copending application Serial No. 382,985, filed September 29, `1953, on Method of and Apparatus for Making Molded Pulp Articles which on May 3l, 1960 matured into Patent No. 2,938,582.

Said parent application the disclosure of which is herein incorporated by reference, discloses integrated apparatus and methods for forming pulp articles and comprises all apparatus and method steps, from initially suction forming an article on a suction die, to and including the discharge of such article from the apparatus in condition to be packed for the market. That apparatus and method embody, inter alia, means operable upon a freshly molded suction formed pulp article for reshaping and consolidating a portion of said article, generally the peripheral edge thereof, so that the resulting end product will have a thickened reinforced edge of strong, neat and pleasing appearance. The means for accomplishing this result embodies certain die structures which form the subject matter of the present application. The die structures of this invention may be employed in reshaping a wide variety of freshly molded pulp articles and, while useful in the integrated machine of the parent application aforesaid, may be used in other apparatus and in other combinations than in the particular apparatus disclosed in said parent application.

The primary object of this invention is to provide novel die structures for reshaping and consolidating the brous materials of a portion of a freshly molded fibrous article into a compact, strong, vhomogeneous structure after the brous materials have been transformed from liquid to a semi-solid state or condition and while the pulp of such article is still wet.

Features of the invention, other than those adverted to, will be apparent from the hereinafter detailed description and appended claims, when read in conjunction with the accompanying drawings.

The accompanying drawings illustrate different practical embodiments of the invention, but the constructions therein shown are to be understood as illustrative, only, and not as dening the limits of the invention.

FIG. l is a vertical longitudinal section of an integrated pulp molding machine with certain parts in elevation. This figure corresponds to FIG. 3 of the parent application and shows certain dies, the structures of which constitute the subject matter of this divisional application.

FIGS. 2-9 are fragmental diametric sectional views wherein:

FIG. 2 illustrates a forming die shown in FIG. l with a wet formed article thereon.

FIG. 3 shows a transfer die in cooperation with a forming die as shown in FIG. 2.

FIG. 4 shows the transfer die of FIG. 3 removed from the forming die and supporting a formed article thereon.

FIG. 5 shows the transfer die of FIG. 4 cooperating with a take-olf die, with the formed pulp article between said dies.

FIG. 6 corresponds to FIG. 5, but shows the parts of the two dies in the act of reshaping the edge of the article.

FIGS. 7 and 8 shows modified forms of the mechanism lee ticles having reshaped adges formed by the dies shown in FIGS. 5 and 6.

Referring to FIG. l of the drawings, `3 indicates a pulp containing tank above which is a horizontal shaft 4 supporting a forming drum 8 provided about its periphery with a succession of suction forming dies 9. As the drum is rotated, the dies are caused to successively dip into the pulp of the tank 3 to suction form on said dies an accreted pulp article, hereinafter designated A.

ln the apparatus of FIG. l an article, after being formed on a die 9, moves into cooperation with a solidification die 12. (forming no part of the present invention) and passes from this die into cooperative relation with a transfer die 33 supported on a transfer die carrier 41. The die 33 embodies die structure forming part of this invention.

The transfer die carrier 41 is mounted to travel in cam tracks 43 formed in `levers 44 arranged at opposite sides of the machine and, through this travel under the impulse of the link 46, the transfer die carrier moves from the position shown in full lines in FIG. l to the dotted line position thereof. While in this dotted line position, it cooperates with a take-off die 61 also embodying the invention of this application. Die 61 is mounted on an arm 68 and this arm moves the die 61 from the position shown in dotted lines in FIG. 1 to a position to deposit an article carried by the take-oft" die onto either the conveyor 66 or 67 of a dehydrator 100, all as fully explained in the parent application. Through these various operations, an article A, formed from liquid pulp mixture in From this general description of the operation of the' molding machine, the utility and eliiciency of the die structures of this invention will be more clearly understood. These die structures will now be described in detail.

In FIGS. 3 and 4 transfer die 33 is shown as provided with a main chamber 34 back of its article engaging perforated face and arranged peripherally of this main chamber is a separate annular chamber 35 which is, in effect, an annular cylinder in which a ring like piston 36 is operable. This piston has channels 37 extending upwardly from its lower edge and radially to the inner surface of the piston. These channels `are adapted to register at certain times with the channels 38 leading into the main chamber 34 of the die. The pipe connection 39 to the main chamber 34 of each transfer die provides means for the introduction of either suction or compressed air into the main chamber 34 while a similar means in the form of a pipe connection 40 is provided for the annular chamber 35.

When transfer die 33 engages with an article on a forming die 9, as shown in FIG. 3, and while the transfer die carrier 41 is in the full line position of FIG. l, the main chamber 34 of the transfer die has suction applied through the pipe connection 39. The open ends 37a of the channels 37 are then in contact with the article A on the forming die so that said suction will assist in the removal lof the article from the forming die and its retention on their free edges with appropriate lianges or thickened sections for reinforcing or other purposes. In the apparatus of the present invention, molded material for these sections is formed on the forming dies. The present invention provides means whereby this latter material may be reshaped to constitute an integral reinforcing structure at the edges or other portions of the articles.

In the drawings, I have shown two forms of reshaping mechanisms, namely, that of FIGS. 56 and the modified form of FIGS. 7-9. The structure and operation of the parts therein illustrated will now be explained. In FIGS. 5 and 6, the transfer die 33 is shown as described in connection with FIGS. 3-4, but a novel form of take-off die is illustrated and is so constituted as to provide for reforming of a portion of the article A to produce a reinforced edge.

The take-off die 61 of FIGS. 5 and 6 is provided with a main chamber 120 having a pipe connection 121 through which suction may be provided within the chamber 120 or compressed air may be admitted thereinto. Encircling the main chamber is an annular chamber 122 forming, in effect, an annular cylinder in which is positioned an annular piston 123, in many respects similar to the piston 36 but inverted. The piston 123 has channels 124 extending upwardly from its lower end and then laterally to its inner surface. The connection 125 provides for suction Within the annular cylinder 122 or for the admission of compressed air thereinto. Through the manipulation of the parts described in connection with FIGS. 5 and' 6, a portion of the article may be reformed or reshaped while the transfer and take-olf dies are in the dotted line positions shown in FIG. l, wherein they are in engagement with the upper and lower surfaces, respectively, of the body of such article. Such engagement is insured by a pressure bar 126 (FIG. l), the operations of which are fully disclosed in the parent application.

The actual reforming or reshaping operations according to FIGS. 5 and 6, with respect to these mating dies 33 and 61 are as follows: At the commencement of reforming, the parts appear as in FIG. 5 with the dies in contact with the body of the article, the piston 36 engaging with the upper surface of the article flange a, and said ange resting upon the upper surface of the piston 123 which, at this time, is in lowered position. Suction is now applied to chamber 35 which lifts piston 36 to the position shown in FIG. 6.

With these dies in this relation, compressed air is now admitted to the chamber 122 beneath the piston 123 and, as shown in FIG. 6, this piston is thereby forced upwardly, carrying with it the outer margin of the iiange a, with the result that that margin is upturned as shown at a in FIG. 6, and the ends of pistons 123 and 36 are in contact. -As this operation occurs, compressed air from the chamber 122, traverses the channel 124 and blows the upturned end a from the full line upstanding position of FIGS. 6 and l0 into the dotted line position of FIG. 6, thereby freeing it from frictional contact with the inner surface of piston 123. In other words, this operation tends to fold the margin of the flange inwardly against the body of the article with the result shown in FIG. ll, this being assisted by vacuum applied to chamber 120 which will tend to hold the reshaped ange in this position. This is the preferred shaping of the reinforcing edge in this form of the invention, although, if a reinforcing margin a is desired to be formed' as shown in FIG. l0, this may be accomplished by utilizing only sufiicient air pressure through channels 124 as will free the article from contact with the piston and by lowering the piston 123 immediately thereafter to admit air to the space between the reshaped liange and the body of the article.

Having formed the reinforcing edge as shown in either FIG. l0 or l1, the reforming operation is complete, the pressure bar 126 is withdrawn and compressed air is admitted to one or both chambers 34 and 35 of the transfer die 33. Suction is admitted to the main chamber 120 of the take-off die 61, and the article is thus transferred from the transfer die 33 to the takeoff die 61, which transports the article to and deposits it on one of the conveyors of the dehydrator.

In the modified form of reforming apparatus shown in FIGS. 7, 8 and 9, each of the take-off dies 61 is of the same construction as shown in FIGS. 5 and 6, but each transfer die, designated 33a in these figures, is constructed differently from the corresponding die of the preceding figures. That is to say, instead of having only a single annular chamber 35 and a cooperating piston 36, as in the preceding figures, die 33a has an additional annular chamber 132 about the main chamber 34 of such transfer die. In this added chamber is positioned an annular piston 133 having passage 134 which, in the retracted position of the piston, registers with passages 135 communicating with the main suction-compression chamber 34 of the die.

In operating the type of transfer die 33a of FIGS. 7-9, the mechanism performs initially as described in connection with FIGS. 5 and 6. In other words, the parts function to turn up the margin a of the iiange a of the article A, as shown in FIG. 7. While this is being done, suction is imparted to the chamber 132 through means illustrated as a connection 136 to keep the annular piston 133 elevated. However, as soon as the marginal portion a' of the flange a has been `turned up, as shown in FIG. 7, suction through the connection 136 is discontinued and compressed air is applied through said connection. This forces the piston 133 downwardly against the upturned edge of the margin a' to reform said edge into the tightly compacted form shown at a2 in FIG. 8. The takeoff die then delivers the article to the conveyor 67 of the dehydrator as shown in FIG. 9.

Compressed air and suction for operating die parts as described may be supplied from any appropriate sources through appropriate control valves as disclosed in the parent application or in any other manner common to the pulp molding art.

Experience has shown that the die structures of this invention operate with extremely high efficiency in the carrying out of their intended functions and accomplish these results at relatively high speed and without undesirable deformation of the molded pulp article.

The foregoing detailed description sets forth the invention in its preferred practical forms, but the invention is to be understood as fully commensurate with the appended claims.

Having thus fully described the invention, what I claim as new and desire to secure by Letters Patent is:

l. A die for operating on a molded brous pulp article subsequent to forming, and before dehydration or drying comprising: a die body provided with a suction and cornpressed air chamber one wall of which has a contoured article engaging face on its exterior, said body being also provided with a pneumatic cylinder surrounding said chamber and opening at the contoured side of the die body, and a piston operable in said cylinder.

2. A die according to claim l, wherein the piston has passages leading from its outer end of the inner face of the piston, said passages being adapted to register with passages leading to the interior of the chamber when the piston is in advanced position.

3. A die for operating on a molded fibrous pulp article subsequent to forming and before dehydration or drying comprising: a die body provided with a suction and compressed air chamber one wall of which has a contoured article engaging face on its exterior, said body being also provided with two pneumatic cylinders respectively surrounding said chamber and opening at the contoured side of the die body, and a piston operable in each cylinder.

4. A die according to claim 3, wherein said pistons have passages leading from their outer ends to the inner faces thereof, said passages being adapted to register with each other and with a passage leading to the chamber when said pistons are in predetermined positions.

5. A die for operating on a molded iibrous pulp article subsequent to forming and before dehydration or drying comprising: a die body provided with a contoured article engaging face on its exterior, and a pneumatically operable sleeve-like piston carried by said body marginally of said `article engaging face.

6. A die according to claim 5, wherein the article engaging face is circular and the sleeve-like piston is also lcircular and coaxial with said face.

7. A die for operating on a molded iibrous pulp article subsequent to forming and before dehydration or drying comprising: a die body provided with a contoured article engaging face on its exterior, and a plurality of pneumatically operable sleeve-like pistons carried by said body marginally of said contoured article engaging face.

8. A die `according to claim 7, wherein said pistons are coaxial with one another and with the contoured article engaging surface.

9. A die rfor operating on a molded fibrous pulp article subsequent to forming `and before dehydration or drying comprising: a die body provided with a contoured article engaging face, a pneumatic cylinder extending into the body marginally of and about the article engaging face thereof, a sleeve-like piston in said cylinder, and a pneumatic connection through ywhich pneumatic pressure and partial vacuum may be seletcively communicated to said cylinder to operate the piston.

10. A die for operating on a molded fibrous pulp article subsequent to forming and before dehydration or drying comprising: a die body provided with a contoured article engaging face, a plurality of coaxial pneumatic cylinders extending into the body marginally of and about rthe article engaging surface, a sleeve-like piston in each cylinder, and a pneumatic connection through Which pneumatic pressure and partial vacuum may be selectively communicated to each cylinder to operate the piston therein.

11. A die couple for operating on ya molded fibrous pulp article subsequent to forming and before dehydration or drying, each member of which couple comprises: a body having a contoured article engaging face complementary to the article engaging face of the body of the other member of the couple, and each die body also having ra pneumatically operable sleeve-like piston marginally of its article engaging face to respectively act upon the opposite sides of the margin of a pulp article positioned between the article engaging faces of the two members of the couple.

l12. A die couple according to claim 111, wherein the pistons of the two members of the couple are positioned to substantially register with one another on the opposite sides of the margin of the article.

13. A die couple according to claim 12, wherein the body of one member of the couple has an additional pneumatically operable sleeve-like piston positioned to act upon the margin of the article contiguously to and ou-t of register with the other pistons and between the zone of operation of said other pistons and the contoured article engaging faces of the members of the couple.

14. A die couple according to claim 12, comprising: passages in the several pistons leading to the article engaging ends thereof for applying compressed air or partial vacuum to the Iarticle at said ends.

15. A die couple according to claim 11, comprising: passages in the several pistons leading to the article engaging ends thereof `for applying compressed air or partial vacuum to the article at said ends.

16. A die couple for operating on a molded librous pulp article subsequent to forming and before dehydration or drying, one member of which couple comprises: a die body having a contoured article engaging face, a pneumatically operable piston marginally of and about the article engaging face thereof for deecting the margin of an article on said article engaging face into substantially normal relation to the plane of symmetry of said face.

17. A die couple for operating on a molded fibrous pulp article subsequent to forming and before dehydration or drying, one member of which couple comprises a die body having a contoured article engaging face, a pneumatically operable piston marginally of and about the article engaging face thereof 4for deflecting the margin of an article on ysaid article engaging face into substantially normal relation to the plane of symmetry of said face, and the other member of which couple comprises a die body having a contoured article engaging face complementary to the article engaging face of the body of the first mentioned member of the couple and having a pneumatically operable sleeve-like piston marginally of its article engaging face to reshape the deflected marginal portion of the article between the members of the die couple into a thickened reinforcing edge about the margin of the article.

18. A die couple for operating on a molded brous pulp article subsequent to forming and before dehydration or drying, one member of which couple comprises: a die body having a contoured article engaging face, a pneumatically operable piston marginally of and about the article engaging face thereof for deflecting the margin of an article on said article engaging face into substantially normal relation to the plane of symmetry of said face, and a compressed air duct extending through the piston and into juxtaposition with the deflected margin of the article to communicate compressed air to said deflected margin for the purpose of reshaping it into a reinforcing edge about the margin of the article.

References Cited in the file of this patent UNITED STATES PATENTS 1,884,708 .leneson Oct. 25, 1932 2,377,351 Martin June 5, 1945 2,377,864 Chaplin .Tune 12, 1945 2,408,734 Chaplin Oct. 8, 1946 2,697,967 Chaplin Dec. 28, 1954 

